I cant imagine 2 million people speaking at a conference.
Dude, some people have family, some companies have long term futures, where it is secure.
Some companies hire contractors to do the shity boring work, while the best do the design/inventing in house. Why would you give your secrets away to bloody contractors.
Oh and btw, yes contractors are a rip off, 20-30% fees to hire firms. Fuck that.
But some people are rich, and only want to work 2 days a week, or 3 months a year, then contracting is fine.
Never ever think its one way for all people, thats communism. Variety is important.